1. Field of the Invention
The present invention relates to an improved pressure control apparatus with a display means for at least two pressure-wise interconnected pressure vessels and comprising a control chamber having a spring biassed piston member, which control chamber is connected to a fluid feed line provided with a check valve means and is further connected to connection channels intended for connection to said pressure vessels.
2. Description of the Prior Art
The Switzerland Patent Specification No. 570 281 discloses an apparatus for controlling the pressure in one or several motor vehicle tires having the same pressure. The tires, i.e. their inner pressure-air filled spaces are connected by means of channels to a pressure chamber of a control apparatus provided with a valve member. Thereby one of the channels extends directly into the pressure chamber and a further channel extends to the valve seat. The main feature of this known apparatus is that if the tire of the motor vehicle which is connected to the channel extending to the valve seat of the apparatus suffers a damage with a resulting pressure loss, the other tire suffers also a pressure loss and looses pressure until it reaches a value which equals the closing pressure of the valve.
This entails, however, such drawback that in case the defective or damaged tire experiences a pressure rise for instance due to wobbling or rubbing or due to an exposure to the sun, such pressure rise may cause a renewed opening of the valve member causing a further amount of air to flow from the intact tire into the damaged tire until the valve member closes once more. Such an arrangement causes obviously a further pressure loss of the sound tire which may lead to undue operating conditions of the intact tire and finally also to a damaging thereof.